1. Field of the Invention
The present invention generally relates to a printer apparatus and a printer head.
2. Description of the Related Art
For example, a printer issuing a receipt may be widely used for a cash register in a shop, and an Automated Teller Machine (ATM) or a Cash dispenser (CD) in a bank. In issuing the receipt with an exemplary printer, a thermal recording paper may be conveyed as a recording paper and printed by a thermal head at a predetermined position of the thermal recording paper.
In order to print characters or the like on the predetermined position of the recording paper with the printer, it is preferable to accurately determine the positional information of the recording paper. In order for this, the positional information of the recording paper may be detected by a reflecting optical sensor, in which light emitted from a light source onto a recording paper and reflected by the recording paper is detected by a light receiving element such as a photo detector.
There are various recording papers on which characters or the like are printed by a printer apparatus. For example, the recording paper may already have a printed advertisement or may already have an opening portion at a cut line along which the recording paper is to be cut. If the recording paper has an advertisement that has already been printed, the advertisement may have been color-printed. When the recording paper to be further printed, which recording paper already has the color-printed portion, is irradiated by light, light reflected on the color-printed portion and light reflected on a portion other than the color-printed portion have largely different light volumes. Therefore, there may be a case where an accurate position of the recording paper is not detected by a reflecting optical sensor.
In such a printer apparatus, it is preferable to detect the position of the recording paper at a position as close as possible to the thermal head.    [Patent Document 1] Japanese Laid-open Patent Publication No. 2008-19845